A suspicious vehicle prompted the evacuation of several buildings on Capitol Hill today after a motorist struck a police vehicle and barricade in a seemingly intentional act.

After nearly four hours, U.S. Capitol Police said there is "no evidence to indicate any nexus to terrorism at this time" but a suspect faces several charges.

U.S. Capitol Police closed off several streets and detonated two controlled explosions to investigate whether the vehicle contained dangerous materials. At 3:30 p.m., police announced the vehicle was cleared "with negative results."

"At approximately 11:45 a.m., a vehicle was traveling westbound on Independence Avenue when it struck a barrier and a United States Capitol Police (USCP) cruiser at the intersection at Second Street, SE," Eva Malecki, USCP public information officer, said. "The driver was transported to an area hospital with minor injuries. A USCP officer also was transported to the hospital where he was treated for minor injuries and released."

The unidentified driver has been charged with assault with a deadly weapon vehicle, assaulting a police officer felony, aggravated reckless driving, and no valid permit, according to Malecki.

As a light drizzle fell, the first controlled explosion echoed across the Hill at 2:10 p.m. with a loud boom. The second controlled explosion came a short time later to further disrupt the vehicle's trunk and allow officers to inspect it.

The police began establishing a wide perimeter around the vehicle at about 12:00 p.m. and pushed tourists, media and congressional staff away from it. The vehicle was located at Second Street and Independence Avenue, near the Library of Congress.

Security has been elevated near the Capitol since the rise of multiple incidences with police officers.

A 20-year old female driver, Taleah Everett, struck a U.S. Capitol Police cruiser and deliberately hit several officers on March 29 this year near 100 Independence Avenue. A grand jury indicted Everett on an array of charges, including four federal counts of assaulting, resisting or impeding a federal police officer, and three district charges of reckless driving, destruction of property and fleeing of a law enforcement officer. Everett pleaded not guilty to these charges in April but is being held in jail until trial. Everett faces 35 years in prison.

In March 2016, an officer shot 66-year-old Larry Dawson after he was caught, attempting to bring a weapon into the U.S. Capitol visitor center. A female bystander was injured by shrapnel and Dawson was sentenced to 11 months in prison. Dawson had previously been charged with unlawful conduct and assault on a police officer during an outburst in the U.S. House chamber in 2015.

Law enforcement shot and killed 34-year old Miriam Carey on Oct. 3, 2013, after she hit a security barrier and Secret Service officer outside the White House. Carey led police on a chase near the Capitol and had her 1-year-old daughter inside the car. The U.S. Attorney's Office for the District of Columbia found that Carey had not been under the influence of drugs or alcohol, and conducted a review of the incident to decide if pursuing federal criminal civil rights or local charges against the officers from the U.S. Secret Service who killed her would be just. However, the office announced in July 2014 that it found insufficient evidence to pursue a case.